An experimental study of superconvergence phenomena in finite element magnetics

The usefulness of superconvergence phenomena in practical finite element magnetics is investigated. Reports on the superconvergent characteristics of potential-based derivatives at the Gauss-Legendre quadrature points of first-order elements are tested, and Maxwell stress force calculations based on superconvergent integration contours are examined. Results from two experimental studies indicate that derivative superconvergence arises only arbitrarily, or asymptotically with increasing solution accuracy. Overall, the results of this work suggest that superconvergence phenomena, as commonly defined for first-order finite element applications in magnetics, are not apparent in practice.